In the related art, as an example of an image forming apparatus, an ink jet type printer, which performs recording (printing) of an image by discharging ink droplets onto various recording media such as paper or a film and then forming a plurality of dots on a recording medium, is known. The ink jet type printer, for example, alternately repeats a dot forming operation (a pass) for forming dot arrays (raster lines) which are arranged in a line in a main scanning direction of the recording medium by discharging ink droplets with respect to the recording medium from each nozzle while moving (scanning) a head in which a plurality of nozzles are formed in the main scanning direction, and a transport operation for moving (transporting) the recording medium in a sub scanning direction intersecting a main scanning direction. Due to this, dots are arranged in a line without gaps in the main scanning direction and the sub scanning direction of the recording medium, and thereby an image is formed on the recording medium.
In such an ink jet type printer, the quality of a recorded image is improved as the number of times of pass is increased. For this reason, JP-A-2010-17976 discloses an image forming method of dividing a printing area in accordance with an image recorded on the recording medium, and then changing the number of times of scanning for each printing area so as to print an image.